SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '422f58e5770fbcf199204834f219c7bbd64abd3c6759b86be17604f2e830cef7' 
  AND token = '5JNixJqAIbNX7x25hK/jyQVV3OmQFSY/Ui2wHfockFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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