SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cda2cabf464b3f4884f0d1af305bb16f0ae55212dd9d7bef15823bac954df3b' 
  AND token = 'jZBn4kNced0gKBWlkgY0e8c9LgRFEAcyu38TFKInD0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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