SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f78394d8d7a76fb253987a6db696d10118ea58d2f311fc719a071a30fd25087b' 
  AND token = 'fxrsZ4DKFeoMVNNkqApV7/BipO8wfzo9K/fHKPLBr0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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