SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80a28aaf745902dba231114e3ace55866463888f931de8fa8e55583dcb25d557' 
  AND token = 'Bh59yGUg7wA1otCrpyzxGxVPbsTvBQL+DSQYxuDL+w0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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