SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a245901aa3e013dab6099dcbcab5a9f04f577400bdb776cf69c6e8a7aa90b69f' 
  AND token = 'FJWab/5Se2XXl0+p2KZ3wQMxC4BnnutuooQD4qWCWAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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