SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e69bbeeb8c1739ea79130c5e5706aeca96e55e7125236134bf5d791800e3623e' 
  AND token = 'h593qCcdOwyQuqMhjraxAIVsPERJBsHjbuo1phAU7vo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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