SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '177695add4025687e94d82509d47f898d89079986d6e11832b267a39f05dfa9d' 
  AND token = 'e6S5PGMxvv0UQl5UBScmmk/UjBjY2x7Gfg4KxZAOtys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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