SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d10f8a1f644b2d46091af4b07ace90976b59c096c795e6fb3fb4f2638e39558' 
  AND token = 'iBxQWlU5PS3vyVmj2VHPqJRI7aRNIhFYkAXbpqpSFH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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