SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37c63b999d14668f9cea11dc3a82e28081bb44eae99acee5dfa9381ba19848c7' 
  AND token = 'AWA2+FPIb/fI/Uu/+cVEX7ejdyb5tH9zIn4yzaSNGi4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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