SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e77b33f45752690021e5075345537a5e442ceafe495d25cb2e19ca7e05a0601' 
  AND token = '048ZFtjfR94M3FA33yKw44es+T0fop6ajZGgCnTJbRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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