SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ce6963a766cedd29487c5971d132d9b1398244374ba40fac49a824091cf31d4' 
  AND token = 'ri5w4cW1Ys6mOHiNH/OjWa4fvg4VOkFexApQmAaPK0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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