SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '696fb871541ad473dc162b3ec4b696b32c133d66c9ecbf77ee0fd45d27c0a8b6' 
  AND token = 'anhxDNjjMBwMt72yI6tXS9DSUp4UWigggQeSp1IsPj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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