SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecc87400861cc43dd99b991a8f61e80f1a3b73c302fa30ffa4420e4a0db3b76e' 
  AND token = 'GewDTEamLnT0Eu331zJUq8GSLkcD4e/anWqVupVjjI0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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