SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5401fc57a17f87600e0e023bdb7f6af6a5a52dc2824b30e8f5e765885baf9df2' 
  AND token = 'yulFwalGnA1WgkHqpfOdtdsQjTd1qu/KSnFvXNtNeBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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