SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13e29426c2ed608c40b15656a92315a8a1ebddd6e621f9ee5557f9678c7b7df6' 
  AND token = 'FHAM5Vt9CQEG9MyrtpJX9htcguV+oFoTKaUcFeQN4ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}