SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45b5066869370c49248e4e84c6064dc2db9708fa5f6a80716c7d0f82fe0f6464' 
  AND token = 'jxF6cKQbnVoYrygrfpSYo/pBd5kJU1u+HPsulUxumyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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