SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd6b0aef80c1bf3cac03bb1447879f963286be21df36483ba5d8905bfe863f22' 
  AND token = 'EfvWhCNE5Sl46ok9rtWNjmnEpG4x/mIHDm8Y/+bejqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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