SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10c74c9478a64b955927f79fd74f16be3b2c43716cb1c6c780d32935f06116a8' 
  AND token = 'GiyCgejEjlzffQOX2oYXiWjC4JOf6KZWgaaRDsKZM2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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