SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb0b7067d5d93b0b8f4085bcdeb7ae41cc6e568775f6e8b3ca53cb43d4368f3f' 
  AND token = 'tL41Hvng2Sa+2XIU1qmsWEAaTS2L+7+WVnz5GrgYzBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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