SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d24362130791d55acae39366e0a08f27f3a1fac9e26049fcc40877a5486b85a' 
  AND token = 'bYZifWUuhEXW3lm8yVGQ+mDnbAoglgapWUs/BlDstCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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