SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb24819f826f12c26bac7e6dc65582e28dc1443c5cc1554a389b087b3375e872' 
  AND token = 'gihj96YVkzJ4aKNQirRWjIBNqNdR/k02wVRBUPsM7QY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}